1. Field of the Invention
The present invention relates to a structure of trim cover assembly covering a seat back of automotive seat. In particular, the invention is directed to an arrangement of trim cover assembly which is suited for covering the seat back or more suited for covering a rear side of the seat back on which a pocket is provided.
2. Description of Prior Art
As understandable from FIG. 1, there is known a seat back (SB′) of the type comprising a seat back frame (3) made of metallic material, a foam padding (4) and a trim cover assembly (1′), wherein a molding process has been effected to form the padding (4) into a predetermined configuration substantially conforming to an outer contour of seat back, with the seat back frame (3) integrally provided therein, and the trim cover assembly (1′), formed by sewing together plural cover materials into a three-dimensional shape, is securely attached on outer surfaces of the padding (4). Hence, it is to be seen that the trim cover assembly (1′) covers substantially an entire outer surface of the foam padding (4).
In the rear side of the thus-formed padding (4), a flat support plate (6) is resiliently connected by springs (61) with the seat back frame (3) to thereby resiliently support the front region of the padding (4).
As shown, the trim cover assembly (1′) per se is formed with an openable rear cover portion (11′) in the rear side (1′A) thereof, such that the upper end of that rear cover portion (1′A) is only integral with the trim cover assembly (1′), while all other remaining ends thereof are not connected with the latter (1′). Formed in an approximately lower half of such openable rear cover portion (11′) is a pocket (P) adapted for receiving books, leaflets or other small articles. Designations (12′) denotes a pair of rear cover portions which are defined in the rear side of the trim cover assembly (1′) as in FIG. 1 so as to be substantially equal in length to the openable rear cover portion (11′) and spaced apart from each other a distance substantially equal to a breadth of that cover portion (11′). Hence, it is to be seen that, before assembly, the openable rear cover portion (11′) is movable towards the two cover portions (12′) and can be disposed therebetween to close and finish the rear side of the trim cover assembly (1′).
In this conventional seat back, a pair of slide fasteners or zippers (11A) and (11A) are used to engage and disengage the openable rear cover portion (11′) with and from the pair of rear cover portion (12′) and (12′). As seen in FIG. 1, one zipper (11A) is fixedly connected between and along two first lateral ends respectively of the two different rear cover portions (11′) and (12′), while the other zipper (11A) is likewise fixedly connected between and along two second lateral ends respectively of the two different rear cover portions (11′) and (12′).
This sort of seat-back trim cover assembly having an openable rear cover portion with zippers has been disclosed from the Japanese Laid-Open Patent Publication No. 2001-8793 (JP 2001-8793 A). According thereto, a three-dimensional trim cover assembly of seat back is provided, which has, formed in the rear side thereof, a rear cover portion similar to the afore-said openable rear cover portion (11′), so that a pair of slits are defined between that particular rear cover portion and two other rear cover portions of the trim cover assembly in the same manner as described above. A pair of zippers are provided between such rear cover portion and two other rear cover portions in the same manner as described above, to thereby allow that openable rear cover portion to be engaged and disengaged with and from the trim cover assembly. Hence, according to the above-described prior arts, in assembly of seat back, by raising such openable rear cover portion upwardly, the trim cover assembly can be opened wide to provide an opening sufficient to allow a foam padding to be bodily inserted therethrough and placed within the trim cover assembly, and after having placed the foam padding in the trim cover assembly, the openable rear cover portion can be releasably secured by the zippers to the rear side of the trim cover assembly, so that the trim cover assembly may be closed to cover substantially an entirety of foam padding. This effectively makes it easy to cover the padding with the trim cover assembly, thus increasing efficiency and rapidity for attaching a trim cover assembly on a foam padding to form a seat back.
However, the foregoing conventional structure of seat-back trim cover assembly with a pocket provided to the rear side thereof has been with the problem that, when a passenger strongly pulls the pocket (at P) or inserts a large book or a plurality of books or articles in that pocket, both openable rear cover portion (at 11′) and two cover portions (at 12′) engaged therewith via the zippers (at 11A) are forcibly pulled and expanded too much rearwardly from and inwardly of the rear side of the seat back, because of the corresponding excessive great force being applied thereto from the passenger, books or articles, with the result that the zipped portions (at 11A) are forcibly disengaged from each another and opened or deformed meanderingly or sinuously, which undesirably impairs an outer aesthetic appearance of the rear side of seat back.